This invention relates to valve assemblies, valve elements for use in such assemblies, and medico-surgical tubes including such assemblies.
The invention is particularly, though not exclusively concerned with valve elements and valve assemblies for use in medico-surgical tubes of the kind provided with an inflatable cuff around a portion of the tube. In such an application, the valve assembly may be provided at one end of a fluid line making connection with the interior of the cuff.
Valve assemblies for use in such medico-surgical tubes are known in which the assembly includes a resilient housing having a passageway therethrough which is normally blocked by a plug located in the passageway. This known form of valve assembly can be opened by inserting within the passageway the tip of a syringe which engages with projections formed on the inside of the housing and thereby distorts the housing away from the plug to form a gas passageway between the plug and the housing.
While this known form of valve assembly has proved useful on medico-surgical tubes, some users of such tubes prefer not to use valves but instead to close the fluid line to the cuffs by means of a stopper or similar device. It has therefore, until now, been necessary either to manufacture two ranges of medico-surgical tubes, one with valves and one without valves, or to rely on the user himself making somewhat difficult and unreliable adaptations of a tube provided with a valve, according to his preferred method of use.